1. Field of the Invention
The subject invention relates to pressurized gas powered guns, or xe2x80x9cmarkers,xe2x80x9d for firing paintball projectiles. The invention relates more specifically to a particular component of a paintball marker called the firing bolt, and for particular applications, the bolt head.
2. Description of the Related Art
Paintball guns, commonly called markers, are most often used for target practice and mock war games. Paintball war games began gaining popularity as a sport in the early 1980""s, leading to the commercial development of a variety of paintball equipment. The paintball marker uses pressurized air, carbon dioxide, or nitrogen to propel paintball projectiles out the barrel of the gun. The paintball itself is a spherical, brittle gelatin casing containing a paint mixture of ethylene glycol, water and titanium dioxide. The paintball is propelled from the barrel of the gun and designed to rupture on impact with the intended target, for example an opposing paintball war game player.
A number of typical problems occur when firing paintball marker guns. One common problem is that the somewhat fragile paintballs tend to break before they leave the gun, due to excessive bolt impact or gas pressure forces on the ball. Premature ball breakage within the gun barrel results in clogging, shot misdirection, decreased paintball velocity, and a number of other problems, in addition to the cleanup nuisance it creates.
Even without paintball breakage, a number of flaws often hinder the performance and reliability of the paintball marker. The force of the gas impacting the paintball tends to be inconsistent. As a result, shot accuracy is diminished, and distance and velocity are unpredictable. Accommodations must be made for the uncertainty created by the inconsistent gas flow, often resulting in reduced performance. For example, gas pressures must often be regulated at a level lower than the ideal, to allow for the possibility that spikes in pressure might cause the paintball velocity to exceed the allowable limit in war game competition (maximum allowable velocity is usually 300 feet per second). Due to typically inherent inefficient gas flow and inconsistency in impact pressure, paintball marker pressure may be regulated as much as 10% lower than the ideal level for maximum allowable velocity (and therefore, also maximum allowable range).
A number of improvements have been developed for paintball guns in general, as evidenced by a variety of patents issued for inventions related to paintball gun triggers, loaders, air valves, barrels, projectile containers, air reservoirs, and gravity center compensation. Very little improvement has been made, however, in paintball marker bolts, even though the bolt is a critically important component of the system which transfers pressurized gas to the paintball projectile. Bolts have been manufactured with increased inner diameters to maximize the amount of gas flow reaching the projectile, but this modification does not address the turbulent nature of the flow, and therefore doesn""t maximize gas flow efficiency. Bolts have also been custom manufactured for individual consumers"" paintball guns, using very close diametrical tolerances to minimize the opportunity for leakage around the bolt. While this may result in improved flow efficiency, it often requires the gun owner to ship his gun to the manufacturer for measurement so that the bolt can be fabricated to fit the gun precisely. In addition to the inconvenience this causes, it often results in gun jamming, as the unusually close tolerances become too tight when humidity or cold weather causes swelling of the bolt or contraction of the barrel.
As a result, paintball gun performance (i.e. velocity, range, and accuracy) is often not what it otherwise could be. What is needed is a bolt which provides improvement in gas pressure delivery efficiency and consistency, such that maximum allowable pressures (based on maximum allowable velocity) are delivered to the paintball in a reliable and consistently repeatable manner, not only improving shooting accuracy, range, and velocity, but also decreasing the rate of premature paintball breakage inside the gun.
Accordingly, it is an object of the present invention to provide a paintball marker bolt which allows a paintball gun to fire paintball projectiles with minimal premature breakage.
It is another object of the present invention to provide a paintball marker bolt which improves the consistency between shot-to-shot paintball velocity and distance when fired from a paintball marker.
It is yet another object of the present invention to provide a paintball marker bolt which allows a lower gas pressure to be used when firing a paintball marker, as improved velocity and distance makes higher pressure unnecessary.
It is an additional object of the present invention to provide a paintball marker bolt with improved mechanical performance, including better sliding action, less jamming, and improved drive transfer from the paintball gun hammer.
The present invention is an improved paintball marker bolt which accomplishes the objects above. These and other objects will become more readily appreciated and understood from a consideration of the following detailed description of the exemplary embodiment, when taken together with the accompanying drawings.
The preferred embodiment of the subject invention is a marker bolt manufactured from a machinable thermoplastic material. The bolt has a cupped face which matches the paintball curvature, and a plurality of holes in its face geometrically designed to minimize gas flow turbulence and produce a uniform distribution of the pressurized gas which impacts the paintball. An elongated and angled inlet hole ensures alignment with the pressurized gas supply, and begins directing the gas in an angled, partially axial direction within the bolt. A curved air ramp/plug seals the rear of the bolt from leakage, and provides a smooth, non-turbulent transition from angled gas flow to fully axial flow, increasing paintball velocity by as much as 30 feet per second according to users"" test results. An adjustable combination lock and drive pin holds the ramp in place, provides firm drive transfer from the gun hammer, and secures the bolt head to other bolt components. Precision tolerances on external dimensions, combined with a slightly decreased diameter over a portion of the bolt, provide a leak-free seal around the bolt, while decreasing friction during bolt movement. An optional diffuser cone assists in directing flow through the distributing holes in the bolt face. The combination of these components in the preferred embodiment of the present invention provides a significantly improved paintball marker bolt in accordance with the objects outlined above.